/Engine/Plugins/FX/Niagara/Source/NiagaraShader/Public/NiagaraShaderParticleID.h
void NiagaraComputeGPUFreeIDs ( [FRHICommandList](API\Runtime\RHI\FRHICommandList) & RHICmdList, [ERHIFeatureLevel::Type](API\Runtime\RHI\ERHIFeatureLevel__Type) FeatureLevel, [FRHIShaderResourceView](API\Runtime\RHI\FRHIShaderResourceView) * IDToIndexTableSRV, uint32 NumIDs, [FRHIUnorderedAccessView](API\Runtime\RHI\FRHIUnorderedAccessView) * FreeIDUAV, [FRHIUnorderedAccessView](API\Runtime\RHI\FRHIUnorderedAccessView) * FreeIDListSizesUAV, uint32 FreeIDListIndex )